/*
 * ext-imagelib.js
 *
 * Licensed under the Apache License, Version 2
 *
 * Copyright(c) 2010 Alexis Deveria
 *
 */

methodDraw.addExtension("imagelib", function() {

  var uiStrings = methodDraw.uiStrings;
  
  $.extend(uiStrings, {
    imagelib: {
      select_lib: 'Select an image library',
      show_list: 'Show library list',
      import_single: 'Import single',
      import_multi: 'Import multiple',
      open: 'Open as new document'
    }
  });

  var img_libs = [{
      name: 'Demo library (local)',
      url: 'extensions/imagelib/index.html',
      description: 'Demonstration library for SVG-edit on this server'
    }, 
    {
      name: 'IAN Symbol Libraries',
      url: 'http://ian.umces.edu/symbols/catalog/svgedit/album_chooser.php',
      description: 'Free library of illustrations'
    }
  ];
  
  var xlinkns = "http://www.w3.org/1999/xlink";

  function closeBrowser() {
    $('#imgbrowse_holder').hide();
  }
  
  function importImage(url) {
    var newImage = svgCanvas.addSvgElementFromJson({
      "element": "image",
      "attr": {
        "x": 0,
        "y": 0,
        "width": 0,
        "height": 0,
        "id": svgCanvas.getNextId(),
        "style": "pointer-events:inherit"
      }
    });
    svgCanvas.clearSelection();
    svgCanvas.addToSelection([newImage]);
    svgCanvas.setImageURL(url);
  }

  var mode = 's';
  var multi_arr = [];
  var cur_meta;
  var tranfer_stopped = false;
  var pending = {};
  
   window.addEventListener("message", function(evt) {
    // Receive postMessage data
    var response = evt.data;
    
    if(!response) {
      // Do nothing
      return;
    }
    
    var char1 = response.charAt(0);
    
    var svg_str;
    var img_str;
    
    if(char1 != "{" && tranfer_stopped) {
      tranfer_stopped = false;
      return;
    }
    
    if(char1 == '|') {
      var secondpos = response.indexOf('|', 1);
      var id = response.substr(1, secondpos-1);
      response = response.substr(secondpos+1);
      char1 = response.charAt(0);

    }
    
    
    // Hide possible transfer dialog box
    $('#dialog_box').hide();
    
    switch (char1) {
      case '{':
        // Metadata
        tranfer_stopped = false;
        var cur_meta = JSON.parse(response);
        
        pending[cur_meta.id] = cur_meta;
        
        var name = (cur_meta.name || 'file');
        
        var message = uiStrings.notification.retrieving.replace('%s', name);
        
        if(mode != 'm') {
          $.process_cancel(message, function() {
            tranfer_stopped = true;
            // Should a message be sent back to the frame?
            
            $('#dialog_box').hide();
          });
        } else {
          var entry = $('<div>' + message + '</div>').data('id', cur_meta.id);
          preview.append(entry);
          cur_meta.entry = entry;
        }
        
        return;
      case '<':
        svg_str = true;
        break;
      case 'd':
        if(response.indexOf('data:image/svg+xml') === 0) {
          var pre = 'data:image/svg+xml;base64,';
          var src = response.substring(pre.length);
          response = svgCanvas.Utils.decode64(src);
          svg_str = true;
          break;
        } else if(response.indexOf('data:image/') === 0) {
          img_str = true;
          break;
        }
        // Else fall through
      default:
        // TODO: See if there's a way to base64 encode the binary data stream
//        var str = 'data:;base64,' + svgCanvas.Utils.encode64(response, true);
      
        // Assume it's raw image data
//        importImage(str);
      
        // Don't give warning as postMessage may have been used by something else
        if(mode !== 'm') {
          closeBrowser();
        } else {
          pending[id].entry.remove();
        }
//        $.alert('Unexpected data was returned: ' + response, function() {
//          if(mode !== 'm') {
//            closeBrowser();
//          } else {
//            pending[id].entry.remove();
//          }
//        });
        return;
    }
    
    switch (mode) {
      case 's':
        // Import one
        if(svg_str) {
          svgCanvas.importSvgString(response);
        } else if(img_str) {
          importImage(response);
        }
        closeBrowser();
        break;
      case 'm':
        // Import multiple
        multi_arr.push([(svg_str ? 'svg' : 'img'), response]);
        var cur_meta = pending[id];
        if(svg_str) {
          if(cur_meta && cur_meta.name) {
            var title = cur_meta.name;
          }  else {
            // Try to find a title
            var xml = new DOMParser().parseFromString(response, 'text/xml').documentElement;
            var title = $(xml).children('title').first().text() || '(SVG #' + response.length + ')';
          }
          if(cur_meta) {
            preview.children().each(function() {
              if($(this).data('id') == id) {
                if(cur_meta.preview_url) {
                  $(this).html('<img src="' + cur_meta.preview_url + '">' + title);
                } else {
                  $(this).text(title);
                }
                submit.removeAttr('disabled');
              }
            });
          } else {
            preview.append('<div>'+title+'</div>');
            submit.removeAttr('disabled');
          }
        } else {
          if(cur_meta && cur_meta.preview_url) {
            var title = cur_meta.name || '';
          }
          if(cur_meta && cur_meta.preview_url) {
            var entry = '<img src="' + cur_meta.preview_url + '">' + title;
          } else {
            var entry = '<img src="' + response + '">';
          }
        
          if(cur_meta) {
            preview.children().each(function() {
              if($(this).data('id') == id) {
                $(this).html(entry);
                submit.removeAttr('disabled');
              }
            });
          } else {
            preview.append($('<div>').append(entry));
            submit.removeAttr('disabled');
          }

        }
        break;
      case 'o':
        // Open
        if(!svg_str) break;
        methodDraw.openPrep(function(ok) {
          if(!ok) return;
          svgCanvas.clear();
          svgCanvas.setSvgString(response);
          // updateCanvas();
        });
        closeBrowser();
        break;
    }
  }, true);
  
  var preview, submit;

  function toggleMulti(show) {
  
    $('#lib_framewrap, #imglib_opts').css({right: (show ? 200 : 10)});
    if(!preview) {
      preview = $('<div id=imglib_preview>').css({
        position: 'absolute',
        top: 45,
        right: 10,
        width: 180,
        bottom: 45,
        background: '#fff',
        overflow: 'auto'
      }).insertAfter('#lib_framewrap');
      
      submit = $('<button disabled>Import selected</button>').appendTo('#imgbrowse').click(function() {
        $.each(multi_arr, function(i) {
          var type = this[0];
          var data = this[1];
          if(type == 'svg') {
            svgCanvas.importSvgString(data);
          } else {
            importImage(data);
          }
          svgCanvas.moveSelectedElements(i*20, i*20, false);
        });
        preview.empty();
        multi_arr = [];
        $('#imgbrowse_holder').hide();
      }).css({
        position: 'absolute',
        bottom: 10,
        right: -10
      });

    }
    
    preview.toggle(show);
    submit.toggle(show);
  }

  function showBrowser() {

    var browser = $('#imgbrowse');
    if(!browser.length) {
      $('<div id=imgbrowse_holder><div id=imgbrowse class=toolbar_button>\
      </div></div>').insertAfter('#svg_docprops');
      browser = $('#imgbrowse');

      var all_libs = uiStrings.imagelib.select_lib;

      var lib_opts = $('<ul id=imglib_opts>').appendTo(browser);
      var frame = $('<iframe/>').prependTo(browser).hide().wrap('<div id=lib_framewrap>');
      
      var header = $('<h1>').prependTo(browser).text(all_libs).css({
        position: 'absolute',
        top: 0,
        left: 0,
        width: '100%'
      });
      
      var cancel = $('<button>' + uiStrings.common.cancel + '</button>').appendTo(browser).click(function() {
        $('#imgbrowse_holder').hide();
      }).css({
        position: 'absolute',
        top: 5,
        right: -10
      });
      
      var leftBlock = $('<span>').css({position:'absolute',top:5,left:10}).appendTo(browser);
      
      var back = $('<button hidden>' + uiStrings.imagelib.show_list + '</button>').appendTo(leftBlock).click(function() {
        frame.attr('src', 'about:blank').hide();
        lib_opts.show();
        header.text(all_libs);
        back.hide();
      }).css({
        'margin-right': 5
      }).hide();
      
      var type = $('<select><option value=s>' + 
      uiStrings.imagelib.import_single + '</option><option value=m>' +
      uiStrings.imagelib.import_multi + '</option><option value=o>' +
      uiStrings.imagelib.open + '</option></select>').appendTo(leftBlock).change(function() {
        mode = $(this).val();
        switch (mode) {
          case 's':
          case 'o':
            toggleMulti(false);
            break;
          
          case 'm':
            // Import multiple
            toggleMulti(true);
        }
      }).css({
        'margin-top': 10
      });
      
      cancel.prepend($.getSvgIcon('cancel', true));
      back.prepend($.getSvgIcon('tool_imagelib', true));
      
      $.each(img_libs, function(i, opts) {
        $('<li>').appendTo(lib_opts).text(opts.name).click(function() {
          frame.attr('src', opts.url).show();
          header.text(opts.name);
          lib_opts.hide();
          back.show();
        }).append('<span>' + opts.description + '</span>');
      });
      
    } else {
      $('#imgbrowse_holder').show();
    }
  }
  
  return {
    buttons: [{
      id: "tool_imagelib",
      type: "menu", // _flyout
      position: 4,
      panel: "file_menu",
      title: "Image library",
      events: {
        "mouseup": showBrowser
      }
    }],
    callback: function() {
    
      $('<style>').text('\
        #imgbrowse_holder {\
          position: absolute;\
          top: 0;\
          left: 0;\
          width: 100%;\
          height: 100%;\
          background-color: rgba(0, 0, 0, .5);\
          z-index: 5;\
        }\
        \
        #imgbrowse {\
          position: absolute;\
          top: 25px;\
          left: 25px;\
          right: 25px;\
          bottom: 25px;\
          min-width: 300px;\
          min-height: 200px;\
          background: #B0B0B0;\
          border: 1px outset #777;\
        }\
        #imgbrowse h1 {\
          font-size: 20px;\
          margin: .4em;\
          text-align: center;\
        }\
        #lib_framewrap,\
        #imgbrowse > ul {\
          position: absolute;\
          top: 45px;\
          left: 10px;\
          right: 10px;\
          bottom: 10px;\
          background: white;\
          margin: 0;\
          padding: 0;\
        }\
        #imgbrowse > ul {\
          overflow: auto;\
        }\
        #imgbrowse > div {\
          border: 1px solid #666;\
        }\
        #imglib_preview > div {\
          padding: 5px;\
          font-size: 12px;\
        }\
        #imglib_preview img {\
          display: block;\
          margin: 0 auto;\
          max-height: 100px;\
        }\
        #imgbrowse li {\
          list-style: none;\
          padding: .5em;\
          background: #E8E8E8;\
          border-bottom: 1px solid #B0B0B0;\
          line-height: 1.2em;\
          font-style: sans-serif;\
          }\
        #imgbrowse li > span {\
          color: #666;\
          font-size: 15px;\
          display: block;\
          }\
        #imgbrowse li:hover {\
          background: #FFC;\
          cursor: pointer;\
          }\
        #imgbrowse iframe {\
          width: 100%;\
          height: 100%;\
          border: 0;\
        }\
      ').appendTo('head');
    }
  }
});

